EX(w/o STI)-35
Center Exhaust Pipe
EXHAUST
3. Center Exhaust Pipe
A: REMOVAL
1) Remove the collector cover.
(1) Remove the clips (A).
(2) Hold the shaded area (B) by hand and carefully pull the RH side (C) upward.
(3) Hold the shaded area (D) by hand and carefully pull the LH side (E) upward.
2) Disconnect the ground terminal from battery sensor. <Ref. to NT-5, BATTERY, NOTE, Note.>
3) Lift up the vehicle.
4) Remove the under cover. <Ref. to EI-21, REMOVAL, Front Under Cover.>
5) Disconnect the connector on the front oxygen (A/F) sensor from the engine harness, and remove the clip
(A) which secures the front oxygen (A/F) sensor harness to the water pump pulley cover.
EX-03204
(A)
(B)
(C)
(E)
(D)
(A)
EX-03028
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EX(w/o STI)-36
Center Exhaust Pipe
EXHAUST
6) Disconnect the connector on the rear oxygen sensor from the engine harness, and disconnect the ground
cable from the exhaust pipe cover.
7) Lower the vehicle.
8) Remove the bolts which secure the water pump pulley cover (A) and exhaust pipe stay (B) to the turbo-
charger stay, and remove the water pump pulley cover (A) and exhaust pipe stay (B) from the water pump
and turbocharger stay.
9) Lift up the vehicle.
EX-03126
EX-03037
(A)
(B)
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EX(w/o STI)-37
Center Exhaust Pipe
EXHAUST
10) Remove the nuts which secure the center exhaust pipe (rear) to the center exhaust pipe (front).
11) Remove the bolts, springs, and nuts which secure the rear exhaust pipe to the center exhaust pipe (rear).
EX-03127
EX-02971
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EX(w/o STI)-38
Center Exhaust Pipe
EXHAUST
12) Remove the bolt which holds center exhaust pipe (rear) to the hanger bracket, and remove the center ex-
haust pipe (rear).
NOTE:
For CVT model, removing the exhaust pipe bracket from the center exhaust pipe (rear) will adversely affect
the positioning accuracy. Therefore, do not remove the bolts in section (a) shown in the figure.
CVT model
•MT model
EX-03148
(a)
EX-03138
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EX(w/o STI)-39
Center Exhaust Pipe
EXHAUST
13) Remove the exhaust pipe cover (A) from the center exhaust pipe (front), and remove the bolts which se-
cure the turbocharger stay.
14) Using ST, remove the nut (1 place) which secures the center exhaust pipe (front) to the turbocharger.
ST 18283AA010 WRENCH ADAPTER
EX-03014
(A)
EX-02986
ST
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EX(w/o STI)-40
Center Exhaust Pipe
EXHAUST
15) Remove the nuts (3 places) which secure the center exhaust pipe (front) to the turbocharger.
16) Using the TORX
®
socket E10, remove stud bolts (3 places) from the turbocharger, and remove the cen-
ter exhaust pipe (front) together with turbocharger stay (A).
EX-03060
EX-03061
(A)
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EX(w/o STI)-41
Center Exhaust Pipe
EXHAUST
B: INSTALLATION
1) Set the center exhaust pipe (front) together with turbocharger upper stay (A), and install stud bolts (3 plac-
es) to the turbocharger by using the TORX
®
socket E10.
NOTE:
Use a new gasket.
Tightening torque:
14.7 N·m (1.5 kgf-m, 10.8 ft-lb)
2) Temporarily tighten the nuts (3 places) which secure the center exhaust pipe (front) to the turbocharger to-
gether with the turbocharger upper stay (A).
NOTE:
Use a new self-locking nut.
EX-03061
(A)
EX-03062
(A)
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EX(w/o STI)-42
Center Exhaust Pipe
EXHAUST
3) Using ST, install the nut (1 place) which secures the center exhaust pipe (front) to the turbocharger.
NOTE:
Use a new self-locking nut.
ST 18283AA010 WRENCH ADAPTER
Tightening torque:
Calculation formula
T = L/(120 mm (4.72 in) + L) × 42.5 N·m (4.3 kgf-m, 31.3 ft-lb)
T: Tightening torque
L: Effective length of torque wrench
NOTE:
If the effective length of the torque wrench used is unknown, consult the manufacturer of the torque wrench.
(a) Effective length of the ST
(b) Effective length of the torque wrench
(c) Center of drive angle of the ST
(d) Center of drive angle of the torque wrench
(e) Center of the position where a force is applied by hand
EX-02942
(a)
(e)
(c)
(d)
(b)
EX-02999
ST
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EX(w/o STI)-43
Center Exhaust Pipe
EXHAUST
4) Temporarily tighten the nuts (3 places) which secure the center exhaust pipe (front) to the turbocharger to-
gether with the turbocharger stay (A).
Tightening torque:
42.5 N·m (4.3 kgf-m, 31.3 ft-lb)
5) Install the bolt which secures the turbocharger stay, and install the exhaust pipe cover (A) to the center ex-
haust pipe (front).
Tightening torque:
T1: 7.5 N·m (0.8 kgf-m, 5.5 ft-lb)
T2: 33 N·m (3.4 kgf-m, 24.3 ft-lb)
EX-03062
(A)
EX-03015
T1
(A)
T2
T1
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EX(w/o STI)-44
Center Exhaust Pipe
EXHAUST
6) Install the center exhaust pipe (rear) and temporarily tighten the bolt which holds center exhaust pipe
(rear) to the hanger bracket.
CVT model
•MT model
EX-02917
EX-03138
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EX(w/o STI)-45
Center Exhaust Pipe
EXHAUST
7) Install the bolts, springs, and nuts which secure the rear exhaust pipe to the center exhaust pipe (rear).
NOTE:
Use a new gasket.
Tightening torque:
18 N·m (1.8 kgf-m, 13.3 ft-lb)
8) Install the nuts which secure the center exhaust pipe (front) to the center exhaust pipe (rear).
NOTE:
Use a new gasket.
Tightening torque:
42.5 N·m (4.3 kgf-m, 31.3 ft-lb)
EX-02971
EX-03127
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EX(w/o STI)-46
Center Exhaust Pipe
EXHAUST
9) Tighten the bolts which hold center exhaust pipe (rear) to the hanger bracket.
Tightening torque:
35 N·m (3.6 kgf-m, 25.8 ft-lb)
CVT model
•MT model
10) Lower the vehicle.
EX-02921
EX-03139
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EX(w/o STI)-47
Center Exhaust Pipe
EXHAUST
11) Install the exhaust pipe stay (B) and water pump pulley cover (A) to the turbocharger stay and water
pump, and install the bolts which secure the water pump pulley cover (A) and exhaust pipe stay (B) to the tur-
bocharger stay.
Tightening torque:
T1: 19 N·m (1.9 kgf-m, 14.0 ft-lb)
T2: 33 N·m (3.4 kgf-m, 24.3 ft-lb)
12) Lift up the vehicle.
13) Connect the connector on the rear oxygen sensor to the engine harness, and connect the ground cable
to the exhaust pipe cover.
Tightening torque:
7 N·m (0.7 kgf-m, 5.2 ft-lb)
EX-03042
T2
T1
T1
(A)
(B)
EX-03126
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EX(w/o STI)-48
Center Exhaust Pipe
EXHAUST
14) Secure the front oxygen (A/F) sensor harness to the water pump pulley cover with the clip (A), and con-
nect the front oxygen (A/F) sensor connector to the engine harness.
15) Install the under cover. <Ref. to EI-22, INSTALLATION, Front Under Cover.>
16) Lower the vehicle.
17) Connect the ground terminal to battery sensor. <Ref. to NT-5, BATTERY, NOTE, Note.>
18) Install the collector cover.
C: DISASSEMBLY
1) Remove the front oxygen (A/F) sensor and rear oxygen sensor. <Ref. to FU(w/o STI)-126, REMOVAL,
Front Oxygen (A/F) Sensor.> <Ref. to FU(w/o STI)-128, REMOVAL, Rear Oxygen Sensor.>
2) Remove the exhaust pipe cover from the center exhaust pipe (front) and center exhaust pipe (rear).
(A)
EX-03028
EX-03140
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EX(w/o STI)-49
Center Exhaust Pipe
EXHAUST
D: ASSEMBLY
1) Install the exhaust pipe cover to the center exhaust pipe (front) and center exhaust pipe (rear).
Tightening torque:
T1: 7.5 N·m (0.8 kgf-m, 5.5 ft-lb)
T2: 13 N·m (1.3 kgf-m, 9.6 ft-lb)
2) Install the front oxygen (A/F) sensor and rear oxygen sensor. <Ref. to FU(w/o STI)-126, INSTALLATION,
Front Oxygen (A/F) Sensor.> <Ref. to FU(w/o STI)-129, INSTALLATION, Rear Oxygen Sensor.>
E: INSPECTION
1) Check the connections and welded parts for exhaust leaks.
2) Make sure there are no holes or rusting.
EX-03141
T1
T1
T1
T2
T1
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